Who controlled South Africa after its independence?

The uniting of the Colonies that make up South Africa occurred under British Administration in 1910. It Was made up of The Cape, Natal, Transvaal, and Orange River Colonies. This Administration and many after worked to limit voting rights and political power to whites only.

In 1931 the passing of the Statue of Westminster in the British Parliament opened the way to Independence for The Union of South Africa. It was a Constitutional Monarchy with the British King as Head of State (Represented by a Governor General) and a Prime Minister as Head of Government.

In 1961 a new Constitution was created, the Union was dissolved and South Africa was made a Republic with a titular President as Head of State and a Prime Minister as Head of Government.

The long struggle of Apartheid started in 1948. It got substantial more overt in the 1960s under the new Republican Government. South Africa was divided into "whites" and "coloreds".

In 1983 the position of Prime Minister was abolished and the President became both Head of State and Government. P.W. Botha (a white Afrikaans) was the first to hold this position.

In 1994 after a Constitutional change which allowed more universal franchise Nelson Mandela was elected President.

https://en.wikipedia.org/wiki/South_Africa

https://en.wikipedia.org/wiki/Union_of_South_Africa

https://en.wikipedia.org/wiki/South_Africa

By OCHA, CC BY 3.0, https://commons.wikimedia.org/w/index.php?curid=32650153